Patent GB-559406-A (GB)
Title: Improvements in metal tube or pipe bending jigs
IPC: B21D9/07
Filed: 1942-11-26
Abstract: 559,406. Tube-bending machines. PARKER, A. LA R. Nov. 26, 1942, No. 16781. [Class 83 (iv)] A machine for bending a number of tubes to identical form comprises a frame 8, with a radius block 22 and bending means at one end and guides 5 along which a tube clamp 62 can be moved to present the tube 69 to the block 22, means being provided on the frame, and engageable by the clamp slide 59 to locate the tube relative to the block 22 and so determine the positions of the bends. The block 22 and clamp 29 being in position to align this with the mandrel 16, the first tube of a batch is passed over the mandrel 16, between the block 22, clamp 29 and guide 39 and into the clamp 62 where it is located axially by an internal sleeve or a finger 70. The slide 59 is then moved along the guides 5 until the tube is positioned correctly, relative to the block 22, to begin the first bend and a stop 55, Fig. 2, is moved along a shaft 50 into contact with the slide and is so secured and a bridge 41 is moved along the guides 5 into the plane ot one ot the arms 63, 163 on the clamp 62 and so secured, the clamp being turned until said arm engages a stop 44, Fig. 4, of the bridge. The shaft 50 is then turned through 180 degrees by a handle 52, thus withdrawing the stop 55, the guide 39 is then moved into working position by its slide 35, parallel links 36 and handle 33, and the handle 28 is then operated to clamp the tube to, and bend it about the block 22, which is carried by a pivot 20 adjustable along a slot 19 in a fixed bridge 17. When the desired bend has been formed, as shown in the Figures, a stop 57 is moved into contact with the slide 59 and secured to its shaft 50. This is then returned to its original position, the handles 28, 33 are released, the slide 59 advances through a distance corresponding to the length of straight tube required and a stop 155 is moved to engage the slide and secured and a bridge 46 is moved along the guides 5 into the plane of the arm 63 or 163, according as the next bend is to be at an angle of under or over 180 degrees to the first bend, and so secured. The tube, which is prevented from rotating on its axis by holding the handle 68 during bending, is then turned through the angle required and a stop 49 is moved around the bridge 46 to engage said arm 63 or 163 and secured. The shaft is again turned through 180 degrees to release the slide 59 and the second bend is formed as before these operations and adjustments being continued until all the desired bends have been formed. The tube is then removed, the slide and clamp 62 returned to their initial position as determined by the stops 55, 44 and another tube is inserted, clamped and bent to the same form using the set stops 55, 44, 57, 155, 49, 157, 255, 149 &c. the whole cycle of operations being repeated until all the required tubes are bent. For long tubes the initial position is determined by its free end contacting an arm 77, Fig. 9, axially adjustable on a shaft 73 journalled in the bridge 17, the finger 70 being omitted. The handle 28 may be of cranked form to prevent it from obstructing the tube when making close reverse bends.